Some data center interconnections (DCIS) may employ pre-allocated static wide area network (WAN) optical connections. The pre-allocated capacity between data center (DC) sites may be designed for peak data rate and may be underutilized due to fluctuating traffic demands. The static design of DCI may not be suitable for dynamic allocation of new applications to one DC site out of a plurality of candidate DC sites with associated WAN bandwidth adjustment. For example, a first DC may wish to migrate some workload and/or data on the fly to a second DC for load balancing or fault recovery, which may not be accomplished in an efficient manner by a static DCI.
Software defined networking (SDN) may be a networking paradigm in which data forwarding (e.g. data plane) may be decoupled from control decisions (e.g. control plane), such as routing, resources and other management functionalities. The decoupling may also allow the data plane and the control plane to operate on different hardware, in different runtime environments, and/or operate using different models. In an SDN network, network intelligence may be logically centralized in software-based controllers (e.g. SDN controllers), which may configure network nodes (e.g. via OpenFlow protocol) and control application data traffic flow (e.g. compute optimal network paths) in the SDN network independent of network hardware. There may be a growing interest for network providers or service providers to adopt SDN over an underlying network to provide more flexible and scalable transport SDN networks suitable for DCI.